Hi all,

I'm rebuilding a website for an old client who still has a C5.6 site running. I've created a new site in Concrete5.8.2 using composer, converted the old theme to work on the new site, and now want to try migrating the content. I can't seem to find any way to get a migration tool installed in the 5.8.2 website.

After many attempts (nothing would install with composer, in the end I downloaded a zip and installed it through the packages folder) I figured that the 0.5.4-version is the one I needed (anything newer seems to be for the upcoming Concrete5.9) and it's the only one that will even try to install. However, installation crashes with a Doctrine exception:

Unable to create a proxy for a final class "PortlandLabs\Concrete5\MigrationTool\Entity\Import\AttributeValue\ImportedAttributeValue

This happens because ImportedAttributeValue is apparently a final class (although it looks like an abstract when I look at the code, and that's not allowed either).

If I then go back to the dashboard, it says the package has installed, but I can't find any item anywhere in the dashboard for importing data. Where should that be?

How is it possible that this works at all for anyone? And that googling for this error gives me exactly zero results? There must be something completely different going wrong, right?

I'm a pretty experienced webdeveloper but I'm afraid for this one I'm going to need step by step instructions cause I'm obviously missing something basic. :)

Here's my environment info just in case:
# concrete5 Version
Core Version - 8.5.2
Version Installed - 8.5.2
Database Version - 20190925072210

# Database Information
Version: 10.1.41-MariaDB
SQL Mode: NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

# concrete5 Packages
Migration Tool (0.5.4)

# concrete5 Overrides
themes/JBU-2015/elements/footer.php, themes/JBU-2015/elements/header.php, themes/JBU-2015/elements/header_homepage.php, themes/JBU-2015/elements/header_innerpage.php, themes/JBU-2015/elements/header_projectpage.php, themes/JBU-2015/elements, themes/JBU-2015/fonts/269D0E_0_0.eot, themes/JBU-2015/fonts/269D0E_0_0.ttf, themes/JBU-2015/fonts/269D0E_0_0.woff, themes/JBU-2015/fonts/Capsuula-webfont.eot, themes/JBU-2015/fonts/Capsuula-webfont.svg, themes/JBU-2015/fonts/Capsuula-webfont.ttf, themes/JBU-2015/fonts/Capsuula-webfont.woff, themes/JBU-2015/fonts/Exotica-webfont.eot, themes/JBU-2015/fonts/Exotica-webfont.svg, themes/JBU-2015/fonts/Exotica-webfont.ttf, themes/JBU-2015/fonts/Exotica-webfont.woff, themes/JBU-2015/fonts/sosa-regular-webfont.eot, themes/JBU-2015/fonts/sosa-regular-webfont.svg, themes/JBU-2015/fonts/sosa-regular-webfont.ttf, themes/JBU-2015/fonts/sosa-regular-webfont.woff, themes/JBU-2015/fonts, themes/JBU-2015/images/sponsors/ABN-AMRO logo-280.jpg, themes/JBU-2015/images/sponsors/ABN-AMRO logo.jpg, themes/JBU-2015/images/sponsors/ABN-AMRO-280.png, themes/JBU-2015/images/sponsors/ABN-AMRO.png, themes/JBU-2015/images/sponsors/BRU logo-280.png, themes/JBU-2015/images/sponsors/BRU logo.png, themes/JBU-2015/images/sponsors/GE-280.png, themes/JBU-2015/images/sponsors/VBK logo.png, themes/JBU-2015/images/sponsors/VBK-rgb.jpg, themes/JBU-2015/images/sponsors/aon-280.jpg, themes/JBU-2015/images/sponsors/banner-vbk-jongebalie-a.gif, themes/JBU-2015/images/sponsors/nwk.gif, themes/JBU-2015/images/sponsors/rabo-280.png, themes/JBU-2015/images/sponsors, themes/JBU-2015/images/bg2_mini color.jpg, themes/JBU-2015/images/bg2_mini.jpg, themes/JBU-2015/images/bg3_mini color.jpg, themes/JBU-2015/images/bg3_mini.jpg, themes/JBU-2015/images/bg4_mini.jpg, themes/JBU-2015/images/bg_mini color.jpg, themes/JBU-2015/images/bg_mini.jpg, themes/JBU-2015/images/gun.png, themes/JBU-2015/images/logo-jbmn-wit.png, themes/JBU-2015/images/pattern.png, themes/JBU-2015/images/square.png, themes/JBU-2015/images/status.gif, themes/JBU-2015/images, themes/JBU-2015/js/jquery.cookie.js, themes/JBU-2015/js/jquery.js, themes/JBU-2015/js/jquery.lame.js, themes/JBU-2015/js/jquery.masonry.min.js, themes/JBU-2015/js/scroll.js, themes/JBU-2015/js/selectivizr.js, themes/JBU-2015/js/tabbedContent.js, themes/JBU-2015/js, themes/JBU-2015/blog_entry.php, themes/JBU-2015/blog_entry_fullpage.php, themes/JBU-2015/blog_index.php, themes/JBU-2015/blue.css, themes/JBU-2015/contact.php, themes/JBU-2015/default.php, themes/JBU-2015/gold.css, themes/JBU-2015/homepage.php, themes/JBU-2015/ie.css, themes/JBU-2015/ie9.css, themes/JBU-2015/portfolio2.php, themes/JBU-2015/red.css, themes/JBU-2015/simple.php, themes/JBU-2015/stylesheet.css, themes/JBU-2015/thumbnail.png, themes/JBU-2015/typography.css, themes/JBU-2015/view.php, themes/JBU-2015/page_theme.php, themes/JBU-2015

# concrete5 Cache Settings
Block Cache - On
Overrides Cache - On
Full Page Caching - Off
Full Page Cache Lifetime - Every 6 hours (default setting).

# Server Software
nginx/1.16.1

# Server API
fpm-fcgi

# PHP Version
7.3.17

# PHP Extensions
bcmath, bz2, calendar, cgi-fcgi, Core, ctype, curl, date, dom, exif, fileinfo, filter, ftp, gd, gettext, hash, iconv, intl, json, libxml, mbstring, mcrypt, mysqli, mysqlnd, openssl, pcre, PDO, pdo_mysql, pdo_sqlite, Phar, posix, Reflection, session, shmop, SimpleXML, soap, sockets, SPL, sqlite3, standard, sysvmsg, sysvsem, sysvshm, tokenizer, uploadprogress, wddx, xml, xmlreader, xmlrpc, xmlwriter, xsl, Zend OPcache, zip, zlib

# PHP Settings
max_execution_time - 30
log_errors_max_len - 1024
max_file_uploads - 20
max_input_nesting_level - 64
max_input_time - 60
max_input_vars - 1000
memory_limit - 128M
post_max_size - 8M
upload_max_filesize - 2M
mbstring.regex_stack_limit - 100000
mysqli.max_links - Unlimited
mysqli.max_persistent - Unlimited
pcre.backtrack_limit - 1000000
pcre.recursion_limit - 100000
session.cache_limiter - <i>no value</i>
session.gc_maxlifetime - 7200
soap.wsdl_cache_limit - 5
opcache.max_accelerated_files - 4000
opcache.max_file_size - 0
opcache.max_wasted_percentage - 5